export default function reqHeader() {
    var hexcase = 0; /**/ /* hex output format. 0 - lowercase; 1 - uppercase        */
    var chrsz = 8; /**/ /* bits per input character. 8 - ASCII; 16 - Unicode      */
  
    function hex_sha1(s) {
      return binb2hex(core_sha1(AlignSHA1(s)));
    }
  
  
    function sha1_vm_test() {
      return hex_sha1("abc") == "a9993e364706816aba3e25717850c26c9cd0d89d";
    }
  
  
    function core_sha1(blockArray) {
      var x = blockArray; //append padding  
  
      var w = Array(80);
      var a = 1732584193;
      var b = -271733879;
      var c = -1732584194;
      var d = 271733878;
      var e = -1009589776;
  
      for (var i = 0; i < x.length; i += 16) //每次处理512位 16*32  
      {
        var olda = a;
        var oldb = b;
        var oldc = c;
        var oldd = d;
        var olde = e;
  
        for (var j = 0; j < 80; j++) //对每个512位进行80步操作  
        {
          if (j < 16) w[j] = x[i + j];
          else w[j] = rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1);
  
          var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)),
            safe_add(safe_add(e, w[j]), sha1_kt(j)));
          e = d;
          d = c;
          c = rol(b, 30);
          b = a;
          a = t;
        }
  
        a = safe_add(a, olda);
        b = safe_add(b, oldb);
        c = safe_add(c, oldc);
        d = safe_add(d, oldd);
        e = safe_add(e, olde);
      }
      return new Array(a, b, c, d, e);
  
    }
  
  
    function sha1_ft(t, b, c, d) {
      if (t < 20) return (b & c) | ((~b) & d);
      if (t < 40) return b ^ c ^ d;
      if (t < 60) return (b & c) | (b & d) | (c & d);
      return b ^ c ^ d; //t<80  
    }
  
  
    function sha1_kt(t) {
      return (t < 20) ? 1518500249 : (t < 40) ? 1859775393 :
        (t < 60) ? -1894007588 : -899497514;
    }
  
  
    function safe_add(x, y) {
      var lsw = (x & 0xFFFF) + (y & 0xFFFF);
      var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
      return (msw << 16) | (lsw & 0xFFFF);
    }
  
  
    function rol(num, cnt) {
      return (num << cnt) | (num >>> (32 - cnt));
    }
  
  
    function AlignSHA1(str) {
      var nblk = ((str.length + 8) >> 6) + 1,
        blks = new Array(nblk * 16);
      for (var i = 0; i < nblk * 16; i++) blks[i] = 0;
      for (i = 0; i < str.length; i++)
        blks[i >> 2] |= str.charCodeAt(i) << (24 - (i & 3) * 8);
      blks[i >> 2] |= 0x80 << (24 - (i & 3) * 8);
      blks[nblk * 16 - 1] = str.length * 8;
      return blks;
    }
  
  
    function binb2hex(binarray) {
      var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
      var str = "";
      for (var i = 0; i < binarray.length * 4; i++) {
        str += hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8 + 4)) & 0xF) +
          hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8)) & 0xF);
      }
      return str;
    }
  
  
    // ******************
    
    const access_key = '{bYjFzYeGptKzJ8HfJAij4rcfUxkbKmEo}'
    const secret_key = '{dsyVY1CssfeYKz475pnDlgGvHv2BaXt8}' 
  
    const timestamp = new Date().getTime(); // 取时间戳
    const echostr = '8YkFfdJdQgfBA7SWs8T9'; // 随机字符串自行生成
  
    function encrypting(secret_key, echostr, timestamp) {
      // return SHA1(secret_key + echostr + timestamp); // sha1 库自行引入
      return hex_sha1(secret_key + echostr + timestamp);
    }
  
    const requestConfig = {
      headers: {
        "api-signature": encrypting(secret_key, echostr, timestamp),
        "api-echostr": echostr,
        "api-timestamp": timestamp,
        "api-access-key": access_key
      }
    };
    return requestConfig
  }
  